X-Git-Url: https://git.tokkee.org/?a=blobdiff_plain;f=Documentation%2Ftechnical%2Fapi-strbuf.txt;h=afe27599511c5f6bab6e4f799fd18e7d83bdd454;hb=c8a97906bad44c83acfec33e7e0a3bb4b15a716d;hp=985800e43a9b91256c35df60f67c36994142b94c;hpb=4258c212ca2c3674be4b7e00a19db705eee77a48;p=git.git diff --git a/Documentation/technical/api-strbuf.txt b/Documentation/technical/api-strbuf.txt index 985800e43..afe275995 100644 --- a/Documentation/technical/api-strbuf.txt +++ b/Documentation/technical/api-strbuf.txt @@ -12,7 +12,7 @@ strbuf API actually relies on the string being free of NULs. strbufs has some invariants that are very important to keep in mind: -. The `buf` member is never NULL, so you it can be used in any usual C +. The `buf` member is never NULL, so it can be used in any usual C string operations safely. strbuf's _have_ to be initialized either by `strbuf_init()` or by `= STRBUF_INIT` before the invariants, though. + @@ -55,7 +55,7 @@ Data structures * `struct strbuf` -This is string buffer structure. The `len` member can be used to +This is the string buffer structure. The `len` member can be used to determine the current length of the string, and `buf` member provides access to the string itself. @@ -133,8 +133,10 @@ Functions * Adding data to the buffer -NOTE: All of these functions in this section will grow the buffer as - necessary. +NOTE: All of the functions in this section will grow the buffer as necessary. +If they fail for some reason other than memory shortage and the buffer hadn't +been allocated before (i.e. the `struct strbuf` was set to `STRBUF_INIT`), +then they will free() it. `strbuf_addch`:: @@ -197,6 +199,10 @@ character if the letter `n` appears after a `%`. The function returns the length of the placeholder recognized and `strbuf_expand()` skips over it. + +The format `%%` is automatically expanded to a single `%` as a quoting +mechanism; callers do not need to handle the `%` placeholder themselves, +and the callback function will not be invoked for this placeholder. ++ All other characters (non-percent and not skipped ones) are copied verbatim to the strbuf. If the callback returned zero, meaning that the placeholder is unknown, then the percent sign is copied, too. @@ -212,6 +218,13 @@ which can be used by the programmer of the callback as she sees fit. placeholder and replacement string. The array needs to be terminated by an entry with placeholder set to NULL. +`strbuf_addbuf_percentquote`:: + + Append the contents of one strbuf to another, quoting any + percent signs ("%") into double-percents ("%%") in the + destination. This is useful for literal data to be fed to either + strbuf_expand or to the *printf family of functions. + `strbuf_addf`:: Add a formatted string to the buffer. @@ -220,7 +233,7 @@ which can be used by the programmer of the callback as she sees fit. Read a given size of data from a FILE* pointer to the buffer. + -NOTE: The buffer is rewinded if the read fails. If -1 is returned, +NOTE: The buffer is rewound if the read fails. If -1 is returned, `errno` must be consulted, like you would do for `read(3)`. `strbuf_read()`, `strbuf_read_file()` and `strbuf_getline()` has the same behaviour as well. @@ -235,6 +248,11 @@ same behaviour as well. Read the contents of a file, specified by its path. The third argument can be used to give a hint about the file size, to avoid reallocs. +`strbuf_readlink`:: + + Read the target of a symbolic link, specified by its path. The third + argument can be used to give a hint about the size, to avoid reallocs. + `strbuf_getline`:: Read a line from a FILE* pointer. The second argument specifies the line @@ -246,3 +264,9 @@ same behaviour as well. comments are considered contents to be removed or not. `launch_editor`:: + + Launch the user preferred editor to edit a file and fill the buffer + with the file's contents upon the user completing their editing. The + third argument can be used to set the environment which the editor is + run in. If the buffer is NULL the editor is launched as usual but the + file's contents are not read into the buffer upon completion.